SU1364868A1 - Method of measuring thickness of dielectric article - Google Patents

Abstract

The invention relates to a measurement technique and can be used for non-destructive quality control and for determining the thickness of dielectric products. The purpose of the invention is to increase the measurement accuracy by reducing the error in the distance from the radiators to the product. In article 10, electromagnetic waves are first emitted and receive reflected. Then, ultrasonic waves are emitted into the product by a transducer 6 with a directivity characteristic identical to the directivity characteristic of the electromagnetic antenna 3, from the same point and in the same direction as in the emission of electromagnetic waves. Reflected ultrasound waves are also received and the morbidity of reflected ultrasound and electromagnetic waves is measured. The thickness of the product is judged by the ratio of measured values. 1 il. i (L

Description

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11364868

The invention relates to a measurement technique and can be used in industry for non-destructive quality control and to determine the wall thickness of dielectric products. R

The purpose of the invention is to increase the measurement accuracy by reducing the error from the change in the distance of the radiators to the product.

The drawing shows a diagram of the device that implements the method.

The device contains an electromagnetic wave generator 1 connected

d is the thickness of the product;

j I;

 - dielectric constant A - wavelength; 11 7i Frenel coefficients.

To align the position of the ultrasonic receiving and transmitting element with the antenna of electromagnetic waves 10, after measuring the power of the reflected electromagnetic signal, the antenna 3 is shifted to the side, and the receiving and transmitting transducer 6 of ultrasonic waves is installed in its place, through the circulator 2, to the antenna 3, with 5. directionality is greater than the second circulator output of the ultrasonic transducer 6 to detector 4, the ultrasound generator 5 is chosen identical to the characteristic of sound connected to the transceiver An ultrasonic wave transducer 6 connected to the detector 2o 5 is fed to the transmitter and receiver 7. The outputs of the detectors 4 and 7 connect the transducer 6, emit and receive to the first and second inputs of the ratio calculation unit 8, the output of which is connected to the indicator 9. On the contrary

The antennas 3 and the transducer 6, the size 25, measure its power, the value of which is measured by the product 10. The cut is fed to the second input of the antenna 8 directionality unit.

Ultrasonic signal from a generator

wipe ultrasonic waves reflected from the product 10. With the Converter 6, the signal enters the detector 7, where

The method is carried out as follows.

Electromagnetic radiation from generator 1 is fed to antenna 3, which forms a narrow measuring beam of electromagnetic waves. This beam is reflected from the object and enters the antenna 3, from where through the circulator 2 it is fed to the detector 4 electromag-

waves, whose signal is proportional to the power of the received radiation. From the detector 4, a signal is supplied to the first input of the ratio calculation unit 8. The power of electromagnetic waves arriving at the antenna 3 is proportional to the magnitude 1

- 35

40

where f, (in) - the directivity of the receiving-transmitting transducer 6 ultrasound. The ratio of the power of the reflected electromagnetic and ultrasonic waves is proportional to the value

 / Dfa / 2 1

- (d) / P (g; t

PI - (2r) J f, (0.) / R (d) / SPri f, (e,) f, (e,), i.e. isdg - distance from phase centrality of directivity characteristics

antenna to the point of the mirror ultrasound transducer 6

reflection; and electromagnetic antenna 3, we get f, (b is the directivity of antenna 3 of electromagnetic

pa; -p

.-SP position of the measured product 1U from & „- direction to the mirror point

antenna 3. which allows

reflection;

- generalized Fresnel coefficient equal to

Rn + Rijl- T + R

R (d)

R (d)

.nR, n

55

p

-) /, i.e. The measurement results are not affected by the location of the antenna 3, which makes it possible to increase the accuracy of measurements of the thickness of the product.

Claims (1)

Invention Formula Where  V d is the thickness of the product; j I;  - dielectric constant A - wavelength; 11 7i Frenel coefficients. In order to combine the position of the ultrasonic receiving-transmitting element with the antenna of electromagnetic waves, after measuring the power of the reflected electromagnetic signal, the antenna 3 is set aside, and the receiving and transmitting transducer 6 of the ultrasonic waves is adopted in its place, the directivity pattern of the transducer 6 of the ultrasonic waves is chosen using identical characteristic 5 to the transmitter and transmitter emitter 6, emit and receive To align the position of the ultrasonic receiving and transmitting element with the antenna of electromagnetic waves, after measuring the power of the reflected electromagnetic signal, the antenna 3 is shifted to the side, and the receiving and transmitting transducer of ultrasonic waves 6 is installed in its place. The directional characteristic of the transducer 6 of ultrasonic waves is chosen identical to that of par 5 served on the receiving-transmitting transducer 6, emit and receive directivity of the antenna. Ultrasonic signal from a generator To align the position of the ultrasonic receiving and transmitting element with the antenna of electromagnetic waves, after measuring the power of the reflected electromagnetic signal, the antenna 3 is shifted to the side, and the receiving and transmitting transducer of ultrasonic waves 6 is installed in its place. The directional characteristic of the transducer 6 of ultrasonic waves is chosen identical to that of par 5 served on the receiving-transmitting transducer 6, emit and receive wipe ultrasonic waves reflected from the product 10. With the Converter 6, the signal enters the detector 7, where relation ratio. The power of the reflected ultrasound signal is proportional to one R, - ((,. 35 40 where f, (in) - the directivity of the receiving-transmitting transducer 6 ultrasound. The ratio of the power of the reflected electromagnetic and ultrasonic waves is proportional to the value  / Dfa / 2 1 - (d) / P (g; t and electromagnetic antenna 3, get -P p -) /, i.e. measurement results are not affected by location over the antenna 55 antenna to increase the accuracy of the product. Formula of A method for measuring the thickness of a dielectric product, which consists in emitting electro313648684 receive reflected magnetic antenna, from the same point waves from the product, by parameters in the same direction as when which is judged on the thickness of the product, on the t-radiation of electromagnetic waves, which is due to the fact that, with the ultra-high accuracy, extra-sound waves reflected from the product, the power but the product is emitted by ultrasonic electromagnetic radiation and ultrasound transducer with characteristic ultrasonic waves, and about the thickness of the product directional direction identical to that of the measured electrical direction of the electric field.